Places We Protect

Mary Macdonald Preserve at Horseshoe Harbor


Green trees grow along the sandy shore of a lake. The shore curves into a harbor.
Horseshoe Harbor on Michigan's Keweenaw Peninsula. © Harold E. Malde

At the tip of Michigan’s Upper Peninsula, stunted shrubs and trees cling to ancient bedrock created by Lake Superior’s fierce winds.



Since it was originally established in 1982, the Mary Macdonald Preserve has grown to encompass 1,200 acres, including five miles of Lake Superior shoreline. While the rugged bedrock beach here supports only the toughest of plants such as lichen, the preserve is home to 11 threatened or rare species.

Along the shoreline, a rocky ridge creates a barrier for inland species and slower-growing plants. Just inland from the rock beaches, forest thrives in this cool, moist climate. Balsam fir, white cedar, white spruce, and white birch provide habitat for the black bear, snowshoe hare, peregrine falcon, ruffed grouse, golden-crown kinglet, black-throated green warbler and yellow-rumped warbler. 




Hiking, Snowshoeing, Birdwatching, Swimming and Deer Hunting (by permit)


1,261 acres

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Spotlight on Nature (3:00) Mary Macdonald Preserve at Horseshoe Harbor

Plan Your Visit

  • When to Visit

    This preserve is open year round. However, late summer and early fall are the best times to visit to fully enjoy the beauty of the Keweenaw Peninsula without the irritation of the biting insects that come out in the early summer. 

  • What to Bring

    Hiking boots are recommended for walking the trails and shoreline of this preserve. If you want to visit during the early summer months bring insect repellant to protect against biting insects.

  • Permitted Activities
    • Hiking, skiing, and snowshoeing
    • Bird watching, nature study and photography
    • Swimming
    • Geocaching
    • Kayaks and canoes are permitted on Lake Superior. Vessels must be carried from the parking area.
    • Research projects and educational studies with approved permit
    • Hunting with a Conservancy-issued permit for whitetail deer
  • Prohibited Activities
    • No rock climbing and rappelling
    • No motorized and non-motorized vehicles
    • No building of new trails
    • No pets
    • No hunting or trapping without a Conservancy-issued permit
    • No removal of plants or animals (alive or dead)
    • No removal of rocks, water or other non-organic materials
    • No camping, bonfires, fireworks or other fires
    • No firewood collecting
    • No littering
  • Hunting

    The Nature Conservancy allows hunting for white-tail deer on this preserve to reduce threats too many deer can pose to the other plants and animals that live here. All hunters are required to receive a permit from the Conservancy as well as a Michigan deer hunting license. Additionally, hunters must report any deer taken from the preserve.

  • Questions

    Have questions about the preserve? Contact Shaun Howard, TNC protected lands project manager in Michigan.

Keep Exploring

From shifting sand dunes to granite bald mountains, explore over 35 preserves and reserves spread across the state of Michigan.

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Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

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